The Standard Surface shader is a physically-based shader capable of producing many types of materials. It includes a diffuse layer, a specular layer with complex Fresnel for metals, specular transmission for glass, subsurface scattering for skin, thin scattering for water and ice, a secondary specular coat, and light emission.

Standard Surface is energy conserving by default. All its layers are balanced so that the amount of light leaving the surface does not exceed the amount of incoming light. For example, as a surface is made more metallic and the specular layer contribution is increased, the diffuse layer contribution is reduced accordingly to ensure energy conservation.

Diffuse and rough (left) to metallic specular (right).

When using layer weights or colors with values higher than 1, energy conservation is broken. It is discouraged to create such materials, as they will not behave predictably under different lighting, and may lead to increased noise and poor rendering performance.

Due to the large number of controls, the Standard Surface shader is split up into several groups. The individual settings for each group are described in more detail in the pages below.

When rendering diffuse surfaces it is very important that the normals of the geometry face in the right direction. In the example below you can see the difference between normals that are facing inwards in the wrong direction (left side) versus those that are facing correctly in the outwards direction (right side).